Battery power supply: Built-in 1200mAh lithium battery, use Type-C charging cable to charge. Color display: current carbon dioxide data, temperature and temperature. 'humidity. The color will change depending on the carbon dioxide content. Easy to use: Long press the inchON OFFinch key for 3 seconds to turn on and off. The product does not need calibration, the boot can be tested 3 in 1: can work as a carbon dioxide concentration detection, thermometer and hygrometer at the same time. Compact and portable: can be taken to the kitchen, living room, bedroom, or when you go out. Widely used and practical, used for epidemic prevention and control to detect CO2 concentration in the population, to control the number of people and avoid the risk of -. Size: about 90* 70*35mm(mm) Color: Black Quantity: 1 piece